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The article presents a paper about bis[2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidin-1-ium] DL-malate. According to the article, a 1:2 salt can be formed from racemic malic acid in which the malate compound is disordered across a centre of inversion. It says that despite of the malic acid being one of the simplest chiral dicarboxylic acids, its role in supramolecular chemistry has not been widely studied.

Looks into the treatment of PtII and PdII complexes as ideal models for studies of square-planar complexes. Interest in the creation of new antitumor PdII complexes such as [Pd(asme)2]; Synthesis of mixed-ligand PdII complexes of a cis-square-planar coordination geometry with nitrogen and oxygen ligand atoms; Deviations of the central metal atoms from the mean plane.

The structures of the title compounds, C12H8N2O7S and C12H8ClNO5S, contain weak C-H···O interactions creating layers of molecules which, taking the conformation of the molecules into account, are arranged in an ABAB sequence. Both structures can be designated, therefore, as ordered racemates of rotameric species. [ABSTRACT FROM AUTHOR]

The title compound, C36H35N5O7S, is found to exist in a nonspirocyclic (ring-opened) form in the crystal, although equilibrium of ring-opened and ring-closed forms (or socalled ring-chain isomerization) is possible in solution. The 4-oxocyclohexa-2,5-diene ring has a flattened sofa conformation. The N···C intramolecular separation of the atoms which would be directly bonded in a ring-closed form is quite short [2.813 (5) Å]. Topological analysis of charge density based on density-functional-theory calculations was used for consideration of shortened intramolecular contacts and indicates a strong attractive bonding interaction between these N and C atoms in the crystal structure. [ABSTRACT FROM AUTHOR]

The crystal structures of dimagnesium disodium decavanadate icosahydrate, Mg2Na2V10O28·20H2O, (I), and trimagnesium decavanadate octacosahydrate, Mg3V10O28·28H2O, (II), have been determined by single-crystal X-ray diffraction. They crystallize with monoclinic (C2/c) and triclinic (P&1macr;) symmetry, respectively. All the Mg2+ cations in (I) and (II) are octahedrally coordinated by six water molecules. The Na+ cations in (I) are coordinated by three water molecules and three O atoms of the decavanadate anions, and link the latter into a three-dimensional network. The decavanadate anions in (II) are not linked to one another. [ABSTRACT FROM AUTHOR]

Unusually large and good-quality single crystals of the synthetic trioctahedral mica KFe32+(Al0.26Fe0.763+Si3)O10(OH)2 [potassium triiron(II) aluminasilaferrate(III) decaoxide dihydroxide] have been grown hydrothermally. X-ray diffraction data measured at 270 and 100 K have been used to refine the crystal structure, including the positions of the H atoms. This synthetic mica is similar to annite, KFe3AlSi3O10(OH)2, and crystallizes with the same monoclinic C2/m symmetry. No phase transition has been observed down to 100 K. At low temperature, the ditrigonal distortion of the mica structure increases markedly, while the octahedral and tetrahedral bond lengths tend to decrease and increase, respectively. A detailed comparison of structural parameters in various Fe-rich micas is presented. [ABSTRACT FROM AUTHOR]

The article describes the structure of ferric sulfate trihydrate synthesized at 403 Kelvin (K) under hydrothermal conditions. Quadruple chains of [Fe2(SO4)3(H2O)3]0∞ composed the structure. Water-sulfate oxygen (O) -- hydrogen (H) ⋯ O hydrogen bonds are said to link this quadruple chains. It concludes that the trihydrate shares the basic structure features present in other phases in the Fe2(SO4)3·nH20 system.

The article presents a study about a two-dimensional network formed by self-associating silver(I) perchlorate with 3-[4-(2-thienyl)-2H-cyclopenta-[d]pyridazin-1-yl]benzonitrile. It describes a network which has the ability to provide opportunities for host-guest chemistry, such as guest molecule loss and absorption or ion exchange. According to the article, a parallelogram-like macrocycle with approximate dimensions of 16.2 x 7.7 Å is contained in this network.

Studies the crystals of the oxyfluorinated gallium phosphate materials of Institut Lavoisier-12 that were synthesized hydrothermally at 453 K under autogenous pressure using propane -1,3-diamine as the structure-directing agent. Reasons why microporous metal phosphates have been studied intensively; Discovery of novel oxyfluorinated extra-large-pore open-framework structures; Consideration of the concentration of the fluoride ions.

Studies the crystals of the oxyfluorinated gallium phosphate materials of Institut Lavoisier-12 that were synthesized hydrothermally at 453 K under autogenous pressure using propane -1,3-diamine as the structure-directing agent. Reasons why microporous metal phosphates have been studied intensively; Discovery of novel oxyfluorinated extra-large-pore open-framework structures; Consideration of the concentration of the fluoride ions.

Crystals of the title complex, [Cu(CN3O2)2(C3H4N2)4], the structure of which has been determined by single-crystal X-ray diffraction at 304 K, appear to be pseudo-merohedrally twinned. Transformation to a monoclinic C-centred cell was necessary in order to derive the twin law. Twin refinement in a triclinic unit cell significantly reduced the R value. The asymmetric unit of the triclinic cell consists of one molecule in a general position and two half entities with the Cu atom on a centre of inversion. The coordination of the Cu atom is quasi-octahedral, with four imidazole N-atom donors in the equatorial plane and two cyano N atoms from the N-nitrocyanamidate anion in axial positions. Owing to symmetry in the centrosymmetric molecules, the trans imidazole ligands are parallel, while those in the non-centrosymmetric molecule make angles of 22.8 (2) and 77.9 (2)°. [ABSTRACT FROM AUTHOR]

The title compounds, C20H24O7 and C40H32O, respectively, are racemic oxepines, the molecules of which contain a chiral axis. Both molecules possess crystallographic C2 symmetry and the seven-membered ring adopts a twistedboat conformation. [ABSTRACT FROM AUTHOR]

The intermediate [Cd(4-PTZ)2(H2O)4] [4-PTZ is 5-(4-pyridyl N-oxide)tetrazolate, C6H4N5O], (I), in the synthesis of 4-HPTZ, (II), from the cycloaddition reaction of 4-cyanopyridine N-oxide with NaN3 in water using CDCl2 as catalyst, was structurally characterized. The unique Cd atom lies on a twofold axis and the coordination geometry of the Cd atom is that of a slightly distorted octahedron, involving four water molecules and two tetrazolate ligands. The catalytic role of the Cd2+ ion in the tetrazole generation reaction stems from the formation of (I). In acidic solution, (I) can be disassociated and the free ligand, (II), can be released. [ABSTRACT FROM AUTHOR]

In polymeric {[Eu(pzdc)(NO3)(phen)(H2O)]·H2O}n [pzdc is 2,3-pyrazinedicarboxylate (C6H2O4) and phen is 1,10-phenanthroline (C12H8N2)], each europium(III) ion is coordinated by seven O atoms (from three pzdc anions, a nitrate anion and a water molecule) and the two N atoms of the phen ligand, resulting in a nine-coordinated europium(III) center with a distorted monocapped square-antiprismatic coordination polyhedron. Four pzdc anions bridge four europium(III) ions, forming a parallelogram unit, the four vertices of which are occupied by the four pzdc anions. Moreover, each parallelogram unit links six other adjacent parallelogram units, forming a two-dimensional network with disordered lattice water molecules. [ABSTRACT FROM AUTHOR]

3β,6β-Dihydroxyolean-12-en-27-oic acid, C30H48O4, a cyto-toxic and apoptosis-inducing oleanane triterpenoid, which was isolated from the rhizome of Astilbe chinensis, consists of a linear array of five fused six-membered rings. The central ring has a slightly distorted half-chair conformation, while the four outer rings adopt chair conformations. Two hydroxy groups and one carboxy group serve simultaneously as hydrogenbond donors and acceptors, forming molecular chains. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C6H8N+·C8HN4O2-, is characterized by three independent ion pairs (A, B and C) in the asymmetric unit. Each ion pair consists of an anion and a cation, and the three ion pairs have similar geometric parameters. All the anions are arranged as dianion dimers via two N-H···O hydrogen bonds and the dimers form one-dimensional columns parallel to the b axis as a result of π-π interactions. The cations are also stacked, in two different ways: one type of stacking consists of alternating A and B cations, while the other type consists of C cations only. Each dianion dimer stack is surrounded by eight stacks of cations and is not connected directly to other dianion stacks. [ABSTRACT FROM AUTHOR]

In molecules of the title compound, C14H12N2O4, the conformation is dominated by an intramolecular N—H···O hydrogen bond in which one of the nitro O atoms is the acceptor. The molecules are linked by paired C—H···O hydrogen bonds [H···O = 2.41 Å, C···O = 3.2990 (17) Åand C—H···O = 156°] into centrosymmetric R2²(14) dimers; these dimers are linked weakly into chains of alternating R2² (14) and R44(40) rings by a second C—H···O hydrogen bond [H···O = 2.55 Å, C···O = 3.5006 (15) Å and C—H···O = 162°]. [ABSTRACT FROM AUTHOR]

In the title compound, C6H18N22+·C4H4O42-·C4H6O4, the components lie on centres of symmetry in space group P&1macr;, such that the asymmetric unit contains three half-molecules. Despite the different mode (with respect to other dicarboxylic acids) adopted by the intermolecular self-interaction of succinic acid derivatives, the overall structure of the title compound consists of anionic layers that are typical of the packing structures exhibited by other dicarboxylic acid analogues. [ABSTRACT FROM AUTHOR]

In the title compound, C10H9N2+·C9H5INO4S-·2H2O, the 4,4'bipyridine molecule is protonated at one of the pyridine N atoms. These moieties self-assemble into a supramolecular chain along the a axis through N-H···N hydrogen bonds. The quinolinol OH group acts as a donor with respect to a sulfonate O atom [O-H···O(sulfonate)] and acts as an acceptor with respect to a C-H group of ferron [C-H···O(hydroxy)], forming a supramolecular chain along the b axis. These two types of supramolecular chains (one type made up of bipyridine motifs and the other made up of sulfoxine motifs) interact via π-π stacking, generating a three-dimensional framework. These chains are further crosslinked by C-H···O hydrogen bonds and O-H···O hydrogen bonds involving water molecules. [ABSTRACT FROM AUTHOR]

The structure of the title compound, 1-ethyl-6-fluoro-1,4dihydro-4-oxo-7-(piperazin-4-ium-1-yl)-1,8-naphthyridine3-carboxylate trihydrate, C15H17FN4O3·3H2O, has a zwitterion of enoxacin and three water molecules in the asymmetric unit. The zwitterions form sheets lying parallel to each other and are hydrogen bonded in a head-to-tail manner. The crystal structure is stabilized by the involvement of O and H atoms from all the water molecules in strong hydrogen bonds. The naphthyridine ring system is essentially planar, with the carboxylate group lying out of this plane at an angle of 26.13 (6)° and the ethyl group oriented at approximately right angles to this plane. The piperazinium ring adopts a chair conformation. [ABSTRACT FROM AUTHOR]

The title compound, C22H30N2O2·H2O, is an 18-membered diaza-crown ether ligand containing two ether O and two aza N atoms. In the macrocyclic ting, the mean N···O distance is 4.526 (4) Å. The macrocyclic inner-hole size, estimated as twice the mean distance of the donor atoms from their centroid, is ∼2.29 Å. [ABSTRACT FROM AUTHOR]

Molecules of (cyclohexylideneamino)oxyacetic acid, C8H13NO3, (I), are linked into centrosymmetric dimers by pairs of O-H···O hydrogen bonds [H···O = 1.84 Å, O···O= 2.6782(12) Å and O-H···O= 178°]. In [chloro(phenyl)methyleneamino]oxyacetic acid, C9H8ClNO3, (II), the molecules are similarly linked into centrosymmetric dimers by pairs of O-H···O hydrogen bonds [H···O=1.79 Å O···O = 2.6329 (17) Å and O-H···O = 176°], and these dimers are weakly linked into chains by a single type of aromatic π-π stacking interaction. [ABSTRACT FROM AUTHOR]

In the title compound, C9H9N2OS+·Cl- , the cations exhibit amidinium-type delocalization of the positive charge. The ions are linked by one O-H···Cl hydrogen bond and two NH···Cl hydrogen bonds into chains of edge-fused R4²(11) rings. The chains are linked into sheets by a π-π stacking interaction. [ABSTRACT FROM AUTHOR]

In the title compound, C13H13NO2, there is polarization of π-electron density from the amine N atom to the acceptor carbonyl groups: as a result, the molecule exists predominantly in an azomethino-1,3-diketone tautomeric form. There is crystallographic evidence that the phenyl ring, although roughly coplanar with the rest of the molecule, is deconjugated with the adjacent π system of the molecule. The cyclohexane ring adopts an unsymmetrical half-chair conformation and converts between two inversion-related conformers. The molecule is stabilized by an intramolecular hydrogen bond, while the intermolecular packing is dominated by a number of short C-H···O contacts. [ABSTRACT FROM AUTHOR]

Tris(2-pyridyl)phosphine oxide, (I), C15H12N3OP, is isomorphous with tris(2-pyridyl)phosphine. Because of a combination of C-H···O and C-H···N interactions, the crystal packing is denser in the title compound than in the related compounds triphenylphosphine oxide and tris(2-pyridyl)phosphine. [ABSTRACT FROM AUTHOR]

In two closely related 1-aryl-2-methyl-4-nitro-5-cyanoimidazoles, namely 2-methyl-4-nitro-1-phenyl-1H-imidazole-5carbonitrile, C11H8N4O2, and 1-(4-chlorophenyl)-2-methyl4-nitro-1H-imidazole-5-carbonitrile, C11H7ClN4O2, different weak intermolecular interactions determine the crystal packing. In the 1-phenyl derivative, dipole-dipole interactions between antiparallel cyano groups connect molecules into centrosymmetric dimers, while in the 1-(4-chlorophenyl) derivative, the dimers are connected by C≡N···Cl-C halogen bonds. These interactions, together with weak CH···O(N) hydrogen bonds, connect molecules related by subsequent centres of inversion into infinite tapes. [ABSTRACT FROM AUTHOR]

The title compound, C10H13NO2, crystallizes with Z' = 2 in space group P&1macr;. The molecules are linked by two O-H···N hydrogen bonds [H···O = 1.97 and 1.98 Å, O···N = 2.810 (2) and 2.815 (2) Å, and O-H···N = 175 and 174°] and by one C-H···O hydrogen bond [H···O = 2.50 Å, C···O = 3.313 (2) Å and C-H···O = 144°] into chains of edge-fused centrosymmetric rings in which R44(16) and R44(24) rings alternate. [ABSTRACT FROM AUTHOR]

The 68.5:31.5 mixture of diastereoisomers obtained in the synthesis of the title compound, C12H16O3, yielded sharply melting crystals containing the same ratio of epimers, in a disordered crystallographic arrangement. The disorder resides almost entirely in the carboxymethyl side chain, but places the two sets of carboxyl O atoms at nearly identical paired spatial positions. Neither component displays significant carboxyl disorder, and the molecules aggregate as hydrogen-bonded carboxyl-to-ketone catemers [O···O = 2.673 (4) Å and OH···O = 158°] having glide-related components, with centrosymmetrically related pairs of chains following axes perpendicular to b. Close intermolecular C-H···O contacts exist for both the ketone and the carboxyl group. The energetics of the epimers and of their crystallization mode are discussed. [ABSTRACT FROM AUTHOR]

In methyl [5-methoxy-4-(4-methoxyphenyl)isochroman-3-yl]acetate, C20H22O5, (I), and methyl [4-(2,5-dimethoxyphenyl)8-methoxyisochroman-3-yl]acetate, C21H24O6, (II), the heterocyelic rings adopt half-chair conformations. The substituents at the 3- and 4-positions are in a trans configuration in hoth (I) and (II), being in an axial conformation in (I) and in an equatorial conformation in (II). The crystal structure of (I) is stabilized by weak C-H···O hydrogen bonding, leading to the formation of an infinite three-dimensional network. Compound (II) crystallizes in a chiral space group. This feature, which was also found in previously investigated isochroman derivatives, is related to the arrangement of substituents attached to the isochroman moiety. [ABSTRACT FROM AUTHOR]

The title compounds, both C19H20FN3O2, contain essentially planar benzoxazolinone ring systems, within which the C-N bond distances and angles do not differ significantly between the two compounds. In both cases, the piperazine ring adopts an almost perfect chair conformation and the benzoxazolinone ring system lies nearly perpendicular to it. The structures contain intermolecular C-H···O contacts, and the interactions between the benzoxazolinone and fluorophenylpiperazine portions of the molecules are segregated. [ABSTRACT FROM AUTHOR]

The title compound, 5-{4-[(2-pyridylideneamino)sulfonyl]phenyldiazenyl}salicylic acid, C18H14N4O5s, crystallizes as the imide tautomer in the monoclinic space group P21/c. In addition to an intramolecular O-H···O hydrogen bond, intermolecular O-H···O interactions link adjacent molecules into helices, which are connected by pairwise NH···N interactions into two-dimensional hydrogen-bonded layers. Both the molecular conformation and the packing differ from those seen in the triclinic amide form [Filip et al. (2001). Acta Cryst. C57, 435-436]. [ABSTRACT FROM AUTHOR]

The title compound, C16H13N3, isolated from Justicia secunda (Acanthaceae), comprises two molecules (which differ slightly in conformation) in the asymmetric unit of space group P&1macr;. Intermolecular Namino-H···Npyrm interactions (Npyrm is a pyrimidine ring N atom) involve only one of the two donor amino H atoms and pyrimidine N atoms per molecule, forming dimeric units via R2²(8) rings, with N···N distances of 3.058 (2) and 3.106 (3) Å, and N-H···N angles of 172.7 (18) and 175.8(17)°. The dimers are linked by C-H···π(arene) contacts, with an H···centroid distance of 2.77 Å and a C-H···centroid angle of 141°. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title complex, [Zn(N3)2(C6H8N6)]n or [Zn(N3)2(bte)]n, where bte is μ-1,2-bis(1,2,4triazol-1-yl)ethane, each Zn atom is pentacoordinated in a distorted trigonal-bipyramidal coordination environment involving two N atoms from two bte ligands and three N atoms from three azide ligands. The Zn atoms are bridged by μ-1,1-azide groups and bte ligands around a centre of inversion, forming an infinite one-dimensional chain containing both four-membered Zn(μ-1,1-N3)2Zn and 18membered Zn(gauche-bte)2Zn rings. [ABSTRACT FROM AUTHOR]

The title compound is a polymeric complex bridged by a phthalate dianion, {[Cd(C8H4O4)(C7H6N2)2(H2O)]·0.5H2O}n. The asymmetric unit contains two Cd complex units, and both CdII atoms have the same distorted octahedral coordination geometry. Each phthalate dianion bridges two Cd atoms through the two terminal carboxy groups, one in a monodentate fashion and the other in a chelating mode, thus forming zigzag polymeric chains; π-π stacking occurs between neighboring chains. The bond angle involving the chelating carboxy group is large, but the corresponding bond distance is normal. This implies the existence of an electrostatic interaction between the CdII atoms and the carboxy groups. [ABSTRACT FROM AUTHOR]

The bimetallic title complex, [CuFe(CN)5(C12H30N6O2)(NO)] or [Cu(L)Fe(CN)5(NO)] [where L is 1,8-bis(2-hydroxyethyl)1,3,6,8,10,13-hexaazacyclotetradecane], has a one-dimensional zigzag polymeric -Cu(L)-NC-Fe(NO)(CN)3-CN-Cu(L)-chain, in which the CuII and FeII centres are linked by two CN groups. In the complex, the CuII ion is coordinated by four N atoms from the L ligand [Cu-N(L) = 1.999 (2)2.016 (2) Å] and two cyanide N atoms [Cu-N = 2.383 (2) and 2.902 (3) Å], and has an elongated octahedral geometry. The FeII centre is in a distorted octahedral environment, with Fe-N(nitroso) = 1.656 (2) Å and Fe-C(CN) = 1.938 (3)1.948 (3) Å. The one-dimensional zigzag chains are linked to form a three-dimensional network via N-H···N and OH···N hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title complex, [Fe(C18H24N10)](ClO4)2·H2O, the complex cation adopts a capped trigonal antiprismatic stereochemistry, with a long Fe-amine interaction [2.7468 (16) Å]. The Fe centre in the asymmetric unit is fully high-spin at 100 K. Hydrogen bonding assembles dimeric units, which are then linked by further hydrogen bonding into chains running parallel to the crystallographic a axis. [ABSTRACT FROM AUTHOR]

In the title compound, [NiCl2(C15H26N2)], the chiral alkaloid (6R,7S,8S,14S)-(-)-L-sparteine acts as a bidentate ligand, with two chloride ligands occupying the remaining coordination sites, producing a slightly distorted tetrahedron. The N-NiN plane in the title complex is twisted by 81.31 (11)° from the Cl-Ni-Cl plane. Other distortions of the tetrahedron are discussed. [ABSTRACT FROM AUTHOR]

The title compound, [Co(C5H11)(C62H88N13O14P)]·0.385C3H6-O·12.650H2O, contains the isoamyl (3-methylbutyl) anion bonded to the CoIII ion through a C atom. The compound is thus a structural analog of the two biologically important vitamin B12 coenzymes adenosylcobalamin and methylcobalamin. The lower axial Co-N bond length [2.277 (2) Å] is one of the longest ever reported for a cobalamin and reflects the strong σ-donor ability of the isoamyl group. [ABSTRACT FROM AUTHOR]

The crystal structures of the tri- and tetrahydrate of tin tetrachloride, viz. diaquatetrachlorotin(IV) monohydrate, [SnCl4(H2O)2]·H2O, and diaquatetrachlorotin(IV) dihydrate, [SnCl4(H2O)2]·2H2O, are reported and shown to contain the cis-[SnCl4(H2O)2] species and water molecules in both cases. The trihydrate contains chains of the tin species linked by a single hydrogen-bonded water molecule, whilst the tetrahydrate has a three-dimensional network. In addition, there are O-H···Cl interactions present. [ABSTRACT FROM AUTHOR]

The title compound, [Cu(C4H12N2)2(C3H6O)2](ClO4)2, is the first structurally characterized CuII complex having acetone as axial ligands. The complex adopts an elongated octahedral trans-[CuN4O2] coordination geometry, with the Cu atom having 222 site symmetry. The axial Cu-O(acetone) and inplane Cu-N bond lengths are 2.507 (5) and 2.041 (3) Å, respectively. [ABSTRACT FROM AUTHOR]

The title compound, [Nd(C10H16O4)(C10H16O4)(H2O)]n, has a novel Nd-organic framework constructed from sebacic acid (C10H18O4) linkers, the longest aliphatic ligand used to date in lanthanide metal-organic framework compounds. The structure contains edge-shared chains of NdO8(H2O) tricapped trigonal prisms that propagate in the [100] direction, with Nd-O distances in the range 2.414 (4)-2.643 (4) Å. [ABSTRACT FROM AUTHOR]

The structure of the title supramolecular complex, [Cu(C7H5O2)2(C5H6N2)2]·0.75C6H6, has been determined. The Cu2+ ion lies on an inversion centre and is coordinated by four O atoms of two opposing benzoate molecules and two pyridine N atoms of two opposing aminopyridine molecules. The partially occupied benzene site lies across a twofold rotation axis. The crystal structure is dominated by twodimensional networks containing two different hydrogenbonded rings [R2²(16) and R4²(8)]. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, [Cu(NCS)(C4H4N2)]n, each Cu atom is coordinated by one N atom of one pyridazine ligand and by one N and two S atoms of three symmetry-related thiocyanate anions within a distorted tetrahedron. Only one N atom of the pyridazine ligand is involved in Cu coordination. The Cu atoms are connected via the thiocyanate anions, forming layers parallel to the ab plane. [ABSTRACT FROM AUTHOR]

In the title compounds, [Pd(C10H6O2)(C10H8N2)], (I), and [Pd(C10H6O2)(C18H12N2)], (II), each PdII atom has a similar distorted cis-planar four-coordination geometry involving two O atoms of the 2,3-naphthalenediolate dianion and two N atoms of the 2,2'-bipyridine or 2,2'-biquinoline ligand. The overall structure of (I) is essentially planar, but that of (II) is not, as a result of intramolecular overcrowding leading to bowing of the biquinoline ligand. [ABSTRACT FROM AUTHOR]

The β-diketone 3-(4-cyanophenyl)pentane-2,4-dione crystallizes as the enol tautomer 4-(2-hydroxy-4-oxopent-2-en-3yl)benzonitrile, C12H11NO2, (I), with an intramolecular OH···O hydrogen bond [O···O = 2.456 (2)Å]. Reaction of (I) with copper acetate monohydrate in the presence of triethylamine leads to the formation of the copper(II) complex bis[3-(4-cyanophenyl)pentane-2,4-dionato-κ²O,O]copper(II), [Cu(C12H10NO2)2], (II). In the structure of (II), the Cu atom is coordinated by four β-diketonate O atoms in a slightly distorted square-planar geometry, with Cu-O distances in the range 1.8946 (11)-1.9092 (11) Å. The nitrile moieties in (II) make it a candidate for reaction with other metal ions to produce supramolecular structures. [ABSTRACT FROM AUTHOR]

Potassium gadolinium polyphosphate, KGd(PO3)4, was synthesized using the flux method. The atomic arrangement consists of an infinite long-chain polyphosphate organization. Two types of chains, with a period of eight PO4 tetrahedra, run along the [101] direction. The Gd atoms have an eightfold coordination, while the K atoms have nine O-atom neighbours. [ABSTRACT FROM AUTHOR]

The structures of the two novel title compounds, Rb2[CrCl5(H2O)], (I), and Cs2[CrCl5(H2O)], (II), have been determined by single-crystal X-ray diffraction. Compounds (I) and (II) crystallize with Pnma and Cmcm symmetry, respectively. In (I), the Cr, three Cl and water O atom lie on a mirror plane; in (II), the Cs, Cr, O and one of the Cl atoms are at sites with m2m symmetry. The chromate anions are in a pseudo-cubic environment of eight Rb+ cations in (I) and in a pseudo-octahedral environment of six Cs+cations in (II). The structural arrangement correlates with the ranion/rcation radius ratio. [ABSTRACT FROM AUTHOR]

The structure of the high-temperature scheelite-type polymorph of cerium niobium tetraoxide, CeNbO4, has been determined using time-of-flight neutron powder diffraction data collected both in sim at 1073 K in air and in vacuo. In both cases, the structure was found to be tetragonal, with I41/a symmetry and without any significant deviation from the stoichiometric composition. [ABSTRACT FROM AUTHOR]

Potassium gadolinium polyphosphate, KGd(PO3)4, was synthesized using the flux method. The atomic arrangement consists of an infinite long-chain polyphosphate organization. Two types of chains, with a period of eight PO4 tetrahedra, run along the [101] direction. The Gd atoms have an eightfold coordination, while the K atoms have nine O-atom neighbours. [ABSTRACT FROM AUTHOR]

The article presents a study about lupulin structures. It mentions the structures of lupulin A and lupulin B which were first elucidated by spectroscopic means and reported as 15Β-methoxy and 2-deoxy-15α-methoxydihydroajugapintin, respectively. As a conclusion, it states that lupulin A should display a revised 15α-methoxydihydroajugapitin anologous to hativene A.